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Hybridization is common in bird populations but can be challenging for management, especially if one of the two parent species is of greater conservation concern than the other. King rails (Rallus elegans) and clapper rails (R. crepitans) are two marsh bird species with similar morphologies, behaviors, and overlapping distributions. The two species are found along a salinity gradient with the king rail in freshwater marshes and the clapper in estuarine marshes. However, this separation is not absolute; they are occasionally sympatric, and there are reports of interbreeding. In Virginia, USA, both king and clapper rails are identified by the state as Species of Greater Conservation Need, although clappers are thought to be more abundant and king rails have a higher priority ranking. We used a mitochondrial DNA marker and 13 diagnostic nuclear single nucleotide polymorphisms (SNPs) to identify species, classify the degree of introgression, and explore the evolutionary history of introgression in two putative clapper rail focal populations along a salinity gradient in coastal Virginia. Genetic analyses revealed cryptic introgression with site‐specific rates of admixture. We identified a pattern of introgression where clapper rail alleles predominate in brackish marshes. These results suggest clapper rails may be displacing king rails in Virginia coastal waterways, most likely as a result of ecological selection. As introgression can result in various outcomes from outbreeding depression to local adaptation, continued monitoring of these populations would allow further exploration of hybrid fitness and inform conservation management. We used genetic analyses to identify species and classify the degree of introgression in putative clapper rail populations along a salinity gradient in Virginia, USA. We found evidence of introgression with higher rates of admixture in the population at the less saline site. We explore the role of ecological selection in this system and compare our results to patterns of introgression in other avian species.

Surveys for secretive marsh birds could be improved with refinements to address regional and species-specific variation in detection probabilities and optimal times of day to survey. Diel variation in relation to naive occupancy, detection rates, and vocalization rates of King (Rallus elegans) and Clapper (R. crepitans) rails were studied in intracoastal waterways in Virginia, USA. Autonomous acoustic devices recorded vocalizations of King and Clapper rails at 75 locations for 48-hr periods within a marsh complex. Naive King and Clapper rail occupancy did not vary hourly at either the marsh or the study area level. Combined King and Clapper rail detections and vocalizations varied across marshes, decreased as the sampling season progressed, and, for detections, was greatest during low rising tides (P < 0.01). Hourly variation in vocalization and detection rates did not show a pattern but occurred between 7.8% of pairwise comparisons for detections and 10.5% of pairwise comparisons for vocalizations (P < 0.01). Higher rates of detections and vocalizations occurred during the hours of 00:00–00:59, 05:00–05:59, 14:00–15:59, and lower rates during the hours of 07:00–09:59. Although statistically significant, because there were no patterns in these hourly differences, they may not be biologically relevant and are of little use to management. In fact, these findings demonstrate that surveys for King and Clapper rails in Virginia intracoastal waterways may be effectively conducted throughout the day.

To minimize wildlife-turbine conflict, the USFWS established voluntary National Wind Energy Guidelines (2003) that recommend an Avian or Avian and Bat Protection Plan (ABPP) for compliance with the Migratory Bird Treaty Act. [...]given the historical distribution of Golden Eagles in eastern North America and the potential negative genetic consequences of translocation programs, we recommend that introductions or translocations of western Golden Eagles into states east of the Mississippi be discontinued.

The Peregrine Falcon was believed to be extirpated as a breeding species in Virginia by the early 1960s. An aggressive restoration program was initiated in 1978 that involved the release of captive-reared birds totaling 115 on the Coastal Plain (1978 1985) and 127 in the Mountain physiographic region (1985–1993). The first occupied territory was established and the first breeding attempt was documented in 1979 and 1982, respectively. We have monitored the size, distribution, reproductive rate, and substrate use of the resulting breeding population (1979 2016). The population proceeded through an establishment phase (1979–1993) driven by releases with an average doubling time of 3.8 yrs to a consolidation phase (1994–2016) with an average doubling time of 23.1 yrs. The state supported 31 breeding pairs by 2016. Per capita reproductive rates have increased significantly over the study period from 0.89 (1979 1993) to 1.86 (1994–2016). Average nesting success increased from 67.1% to 82.7% over the same period. Nesting attempts (n = 469) have been documented on dedicated peregrine towers (52.1%), bridges (26.1%), buildings (4.1%), and various man-made structures (13.0%) with only 4.7% documented on natural cliffs. The population appears to be self-sustaining with reproductive rates exceeding 1.5 young/pair every year since 1999. An ongoing management concern is that only 8.9% of known territories (n = 45) identified since introductions and 4.7% of documented breeding attempts (n = 469) have occurred within the historic mountain breeding range.

Migratory species can experience limiting factors at different locations and during different periods of their annual cycle. In migratory birds, these factors may even occur in different hemispheres. Therefore, identifying the distribution of populations throughout their annual cycle (i.e., migratory connectivity) can reveal the complex ecological and evolutionary relationships that link species and ecosystems across the globe and illuminate where and how limiting factors influence population trends. A growing body of literature continues to identify species that exhibit weak connectivity wherein individuals from distinct breeding areas co-occur during the nonbreeding period. A detailed account of a broadly distributed species exhibiting strong migratory connectivity in which nonbreeding isolation of populations is associated with differential population trends remains undescribed. Here, we present a range-wide assessment of the nonbreeding distribution and migratory connectivity of two broadly dispersed Nearctic-Neotropical migratory songbirds. We used geolocators to track the movements of 70 Vermivora warblers from sites spanning their breeding distribution in eastern North America and identified links between breeding populations and nonbreeding areas. Unlike blue-winged warblers (Vermivora cyanoptera), breeding populations of golden-winged warblers (Vermivora chrysoptera) exhibited strong migratory connectivity, which was associated with historical trends in breeding populations: stable for populations that winter in Central America and declining for those that winter in northern South America.

ContextUnderstanding the factors limiting populations of animals is critical for effective conservation. Determining which factors limit populations of migratory species can be especially challenging because of their reliance on multiple, often geographically distant regions during their annual cycles.ObjectivesWe investigated whether distribution-wide variation in recent breeding population trends was more strongly associated with exposure to risk factors experienced during migration (i.e., natural and anthropogenic threats often associated with increased mortality or carry-over effects) or factors associated with breeding and nonbreeding areas in golden-winged warblers (Vermivora chrysoptera) and blue-winged warblers (V. cyanoptera), two Nearctic-Neotropical migrants experiencing regionally variable population trends.MethodsWe used geolocator data from 85 Vermivora warblers (n = 90 geolocator tracks) tracked from North American breeding locations and Central American nonbreeding locations from 2013 to 2017 to determine variation in space use among populations. We assessed whether differences in space use among populations of Vermivora warblers during migration were associated with exposure to migration risk-factors and whether increased relative exposure to migration risk factors was associated with population declines at regional and subregional scales.ResultsRegional and subregional populations of Vermivora warblers exhibited variation in space use and exposure to anthropogenic and natural risk-factors. However, we found no evidence that recent variation in population trends of Vermivora warblers was associated with risk-factors experienced by different populations during migration. Instead, factors associated with land cover-types in breeding and nonbreeding areas were more strongly associated with recent population trends.ConclusionsUnderstanding how populations of migratory birds are affected by factors experienced during migration is critical for their conservation. We did not find evidence that variation in exposure to migration risk-factors is associated with recent regional or subregional variation in Vermivora warbler population trends. Consequently, our results suggest that efforts to reverse ongoing population declines of Vermivora warblers may be more effective if directed toward conservation actions targeting limiting factors within the breeding and nonbreeding periods versus those directed at conditions encountered during migration. We caution that geographic variation in projected land-use change may differentially affect areas used by different populations of Vermivora warblers during migration, posing a potential threat to these species in the future.

Recent studies of the endangered, cooperatively breeding red-cockaded woodpecker (Picoides borealis) have shown that the number of woodpecker groups in a population is directly dependent on the number of clusters of suitable cavities. Effective management therefore depends on an understanding of the processes underlying the gain and loss of cavities from woodpecker cavity populations. We examined the dynamics of the cavity populations at 4 study sites in North Carolina, USA. All were found to be stable or expanding, but 3 were heavily supplemented by the construction of artificial cavities and the use of cavity restrictors. Cavity losses were due almost entirely to cavity enlargement by other species and to cavity tree mortality. Cavity gains through new excavation were not correlated with cavity losses, and some groups became deficient in cavities. The use of artificial cavities and of cavity restrictors by managers negatively influences natural excavation by red-cockaded woodpeckers, but over the short term, these tools will be necessary to mitigate cavity losses and supplement cavity gains. A long-term management strategy, however, must focus on more effective preservation of the old, living pine trees required by the woodpeckers for cavity excavation.

Background Disadvantaged populations (such as women from minority ethnic groups and those with social complexity) are at an increased risk of poor outcomes and experiences. Inequalities in health outcomes include preterm birth, maternal and perinatal morbidity and mortality, and poor-quality care. The impact of interventions is unclear for this population, in high-income countries (HIC). The review aimed to identify and evaluate the current evidence related to targeted health and social care service interventions in HICs which can improve health inequalities experienced by childbearing women and infants at disproportionate risk of poor outcomes and experiences. Methods Twelve databases searched for studies across all HICs, from any methodological design. The search concluded on 8/11/22. The inclusion criteria included interventions that targeted disadvantaged populations which provided a component of clinical care that differed from standard maternity care. Results Forty six index studies were included. Countries included Australia, Canada, Chile, Hong Kong, UK and USA. A narrative synthesis was undertaken, and results showed three intervention types: midwifery models of care, interdisciplinary care, and community-centred services. These intervention types have been delivered singularly but also in combination of each other demonstrating overlapping features. Overall, results show interventions had positive associations with primary (maternal, perinatal, and infant mortality) and secondary outcomes (experiences and satisfaction, antenatal care coverage, access to care, quality of care, mode of delivery, analgesia use in labour, preterm birth, low birth weight, breastfeeding, family planning, immunisations) however significance and impact vary. Midwifery models of care took an interpersonal and holistic approach as they focused on continuity of carer, home visiting, culturally and linguistically appropriate care and accessibility. Interdisciplinary care took a structural approach, to coordinate care for women requiring multi-agency health and social services. Community-centred services took a place-based approach with interventions that suited the need of its community and their norms. Conclusion Targeted interventions exist in HICs, but these vary according to the context and infrastructure of standard maternity care. Multi-interventional approaches could enhance a targeted approach for at risk populations, in particular combining midwifery models of care with community-centred approaches, to enhance accessibility, earlier engagement, and increased attendance. Trial registration PROSPERO Registration number: CRD42020218357.

BackgroundSpinal cord damage is a feature of many spinocerebellar ataxias (SCAs), but well-powered in vivo studies are lacking and links with disease severity and progression remain unclear. Here we characterise cervical spinal cord morphometric abnormalities in SCA1, SCA2, SCA3 and SCA6 using a large multisite MRI dataset.MethodsUpper spinal cord (vertebrae C1–C4) cross-sectional area (CSA) and eccentricity (flattening) were assessed using MRI data from nine sites within the ENIGMA-Ataxia consortium, including 364 people with ataxic SCA, 56 individuals with preataxic SCA and 394 nonataxic controls. Correlations and subgroup analyses within the SCA cohorts were undertaken based on disease duration and ataxia severity.ResultsIndividuals in the ataxic stage of SCA1, SCA2 and SCA3, relative to non-ataxic controls, had significantly reduced CSA and increased eccentricity at all examined levels. CSA showed large effect sizes (d>2.0) and correlated with ataxia severity (r<−0.43) and disease duration (r<−0.21). Eccentricity correlated only with ataxia severity in SCA2 (r=0.28). No significant spinal cord differences were evident in SCA6. In preataxic individuals, CSA was significantly reduced in SCA2 (d=1.6) and SCA3 (d=1.7), and the SCA2 group also showed increased eccentricity (d=1.1) relative to nonataxic controls. Subgroup analyses confirmed that CSA and eccentricity are abnormal in early disease stages in SCA1, SCA2 and SCA3. CSA declined with disease progression in all, whereas eccentricity progressed only in SCA2.ConclusionsSpinal cord abnormalities are an early and progressive feature of SCA1, SCA2 and SCA3, but not SCA6, which can be captured using quantitative MRI.